Another bump of bone on the foot

Welcome to my foot pain series

The tarsal boss foot bump affects the midfoot and is often called a dorsal spur or osteophyte. This can make management tricky and self-help is more practical in the first place. The patient should understand what the condition is and some of its other problems. This article is slightly more academic, with resources for professionals.  NUMBER TWO most viewed article.

My article foot bump on top of the foot is read widely, so do check it out first.

The condition

A condition that causes pressure on top of the foot due to changes around the middle bones, also known as the tarsus. Conditions associated with the bump include joint surface damage (arthrosis). Tendon or nerve pain that arises with the hard bone bump. Look at the picture of a female foot to identify the problem (source: Bawa 2016).

Naming the condition Other names given to this condition are dorsal spur, exostosis, and tarsal boss. This latter term is quite apt as, in the Collins dictionary, the boss can mean a knob or stud or other circular rounded protuberance.


Recommended source and further reading

https://footeducation.com/tarsal-boss/ My five-star ranked link for Foot Education is recommended. It is impartial with some good writing and knowledge behind the website. Tarsal Boss‘: Edited by Judith Smith MD  October 24, 2017. Previously Edited by Stephen Pinney, MD mf/ 9.23.19


Academic papers

I like to source recent papers and provide a balance between podiatry and orthopaedics. If you like a bit more substance to information, then read on…

Lui 2017 (click on the linked name for the full paper)

Abstract: Dorsal boss of the foot, also known as “tarsal boss,” “dorsal exostosis,” and “humped bone”, is a bone spur that grows from one of the intertarsal or tarsometatarsal joints. It can occur with or without arthritis of the underlying joints. Surgery is indicated if the symptoms do not respond to conservative treatment. Excision of the dorsal boss with or without fusion of the underlying joint is the operative treatment of choice. We report an arthroscopic approach to resection of the dorsal exostosis. Arthroscopic arthrodesis if indicated, can be performed through the same portals.

Bawa 2016 foot bump (click on the linked name for the full paper)

Abstract: A retrospective case series testing the efficacy of surgical resection of the dorsal exostosis deformity of the metatarsocuneiform joints was performed. Surgery was performed on 26 consecutive patients (28 feet) in whom previous conservative therapy had failed. All 26 patients had bursitis at the level of the dorsal exostosis deformity. The patients were separated into 2 groups: group 1, those with bursitis and neuritis before surgery (n 1⁄4 13; 46.4%), and Group 2, those without neuritis (n 1⁄4 15; 53.5%). Both groups were evaluated using an 11-point visual analogue scale administered preoperatively and 1 year postoperatively. The mean pain rating in the patients with neuritis and bursitis before surgery (7.31  2.8) and in those without neuritis (6.67 3.4) decreased to 0 at 6 months and 1 year after surgery. After surgery, 7 patients (25.2%) experienced neuritis. Of these 7 patients, 4 (57.1%) had a continuation of neuritis before surgery, and 3 (42.9%) had an onset of neuropraxia secondary to the surgery itself. This might have resulted from the retraction of the nerves during spur removal. Eventually, all the cases of neuritis resolved. One patient (3.6%) experienced regrowth of their dorsal exostosis deformity, 1 (3.6%) developed an abscess at the surgical site, and 1 (3.6%) developed pain elsewhere at the Lisfranc joint. All patients were subsequently treated at our institution, pain-free, and returned to full activity within 1 year. These results suggest that resectioning the dorsal exostosis deformity of the metatarsocuneiform joints is an effective surgical procedure for patients with this deformity.


The following differential diagnoses can be considered

  • Arthrosis, or joint surface damage.
  • Tendon pain is often associated with overuse.
  • Nerve pain.
  • Ganglion.
  • Bursa.
  • A hard bone bump is also known as a spur.
  • Gout has been recorded, but this is not common in the midfoot so it can be set as a lower priority.

First of all, look at the appearance. The top of the foot will have a bump above the arch, and it can be tender to touch, worse in some shoes. Looking at an X-ray makes it easier to see what is happening. Picture: Dr Van Dalen (click on the name)

The main aim is to take away the pressure, so it comes down to shoe selection and what you can do to the shoe to make matters more comfortable. Remember that the lacings of shoes can be too tight, or the cut of the shoe places too much pressure where it is tender.


  Self-help remedy

Footlocker provides some further information [click here]


Still no better?

Chronic problems: What happens if the problem becomes chronic; that keeps coming back and causing niggly symptoms.

Superficial nerve
First of all, tap the top of the foot, and if the sensation is tender or even electrical, you may have a nerve running over the bump. This is the dorsal medial superficial nerve. A tongue twister at best. Just a word of warning. If the nerve is compressed over the bone and symptoms deteriorate, the nerve will likely thicken and easily repeat those symptoms without much provocation. Protection and shoe selection are vital.

Bursitis
Small sacs filled with lubricating fluid reduce friction and irritation between the bone, tendons, muscle, and skin near your joints, but the development of bursitis can cause pain. It might be worth thinking about having a one-off steroid injection if the area is soft, swollen and not thought infected. Ganglions and bursae are similar, although are actually derived from different tissues. Ganglia are easier to remove the fluid from. 

NB antibiotics should not be used without good reason or evidence of their need.

Seeking surgery
Not perhaps where you want to go, but sometimes surgery is the best way to resolve matters permanently. You should seek out a foot surgeon (podiatric or orthopaedic). Check they are registered with the HCPC or GMC. Here’s a summary of my experience and some things I would tell a patient before surgery.

Surgery

  • The scar line is important, so where the skin is cut can be a problem.
  • The bone is shaved down. If you are under 20, reoccurrence can arise because young people can regenerate bone. This might happen more readily if there is greater movement after surgery as it can all start again or insufficient bone is removed.
  • Although bump surgery can be very effective, wounds can take time. You can expect the skin to heal from 10-21 days before it is relatively strong to get back into shoes. Sensations may vary after surgery, numbness or local sensitivity.
  • The good news is that the surgery works and it is effective.
  • The bad news is that the joint may be less stable, and if you have existing degeneration in the joint movement made by making the joint freer may worsen matters. This means a second surgery to stiffen and fix the problem. This does not happen very often.

Stiffening the toe?
 This means a screw or metal brace (plate) is placed across the joint. On balance, real problems arise from this procedure’s loss of movement around the joint.

So why do I need to have it stiffened?
The spur actually holds the joint stable. The two ends might now move as the surgery involves shaving off the spur. After surgery, and once the foot has healed, you can try out shoes again. It makes sense to allow up to six months for all shoes. Of course, there might be a pair you still cannot use, but on the whole, your comfort and the original problem will have disappeared.


 

Thanks for reading ‘Tarsal Boss’ written by David Tollafield

 

First published Oct. 2019 Updated 23 June 2023

Published by Busypencilcase Reflective Communications Est 2015

%d bloggers like this: